In recent years, there are needs for, improved operating frequency of a logic circuit and low power consumption in a semiconductor integrated circuit device. When the level of a voltage applied to a logic circuit in a semiconductor integrated circuit device increases, operating speed of the logic circuit is improved while power consumption thereof increases. When the level of the voltage applied to the logic circuit decreases, power consumption of the logic circuit decreases while operating speed thereof is reduced.
Based on the relationship between power consumption and operating speed of a logic circuit, a semiconductor integrated circuit device may be provided with a logic circuit receiving a high voltage and a logic circuit receiving a low voltage. For example, a high voltage may be applied to a logic circuit requiring a high-speed operating frequency and a low voltage may be applied to a logic circuit requiring a low-speed operating frequency. Thus, power consumption of the logic circuit may decrease.
In this case, the semiconductor integrated circuit device may be provided with an additional logic circuit receiving both high and low voltages. The additional logic circuit may provide a data communication function between a logic circuit using a high voltage and a logic circuit using a low voltage.